Excel 2003 VBA: Find Method with Variable

My problem is with the line beginning "Selection.Find."

I want it to paste the clipboard contents into the search box, but it's
remembering the specific value used when I set up the macro (i.e. copied the
keystrokes).

    Selection.Copy
    Windows("Master TEST.xls").Activate
    Columns("D:D").Select
    Selection.Find(What:="359", After:=ActiveCell, LookIn:=xlFormulas,
    LookAt _
        :=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext,
        MatchCase:= _
        False, SearchFormat:=False).Activate
    ActiveCell.Offset(0, 1).Select
    Range(ActiveCell, ActiveCell.Offset(0, 1)).Copy
    Windows("New.xls").Activate
    ActiveCell.Offset(0, 1).Select
    ActiveSheet.Paste
    ActiveCell.Offset(1, -1).Select

Thanks for any help